Influence of cobalt precursor and fuels on the performance of combustion synthesized Co3O4/γ-Al2O3 catalysts for total oxidation of methane
Influence of cobalt precursor and fuels on the performance of combustion synthesized Co3O4/γ-Al2O3 catalysts for total oxidation of methane
复制标题
DOI：
10.1016/j.apcata.2007.02.021
复制
发表时间：
2007-04
影响因子：
5.5
通讯作者：
U. Zavyalova;P. Scholz;B. Ondruschka
中科院分区：
文献类型：
--
作者：
U. Zavyalova;P. Scholz;B. Ondruschka
采用湿浸渍和随后的自蔓延燃烧合成（CS）相结合的方法制备了一系列纳米 Co3O4/γ-Al2O3 催化剂。采用 TGA-DTA、红外光谱、N2 吸附-脱附、XRD、SEM/EDX 和 TEM 对浸渍各种钴前体和燃料的氧化铝以及各自的燃烧合成催化剂进行了表征，并在甲烷的全氧化中进行了测试。观察到的初始前体乙酸钴、乙酸钴/硝酸钴的混合物以及硝酸钴与燃料（例如尿素、柠檬酸、甘氨酸和甘油）的混合物对催化性能的影响与其燃烧行为密切相关。发现在合成过程中以最高速度和最低温度燃烧方法获得的催化剂具有最高的活性（甲烷在 400–425°C 下完全转化）。经过两天的反应催化性能，没有观察到燃烧合成催化剂明显失活，并且与硝酸钴热分解制备的样品相比，其粒径仍然小约两倍。
A series of nanosized Co3O4/γ-Al2O3catalysts have been prepared using a combination of wetness impregnation and subsequent combustion synthesis (CS) in self-propagating mode. Alumina impregnated with various cobalt precursors and fuels, and respective as-burnt combustion-synthesized catalysts were characterised by TGA-DTA, IR-spectroscopy, N2adsorption–desorption, XRD, SEM/EDX and TEM, and tested in the total oxidation of methane. The observed influence of the initial precursors cobalt acetate, mixtures of cobalt acetate/cobalt nitrate, and mixtures of cobalt nitrate wit fuels such as urea, citric acid, glycine, and glycerine on the catalytic performance correlates well with their combustion behaviour. Catalysts obtained with the combustion method at the highest velocities and the lowest temperatures during the synthesis were found to have the highest activity (complete conversion of methane at 400–425°C). After two days of catalytic performance in the reaction, no considerable deactivation of combustion-synthesized catalysts was observed and their particle size remained about twice less in comparison with the sample prepared by cobalt nitrate thermal decomposition.